Apparatus for coating metal articles



Nov. 6, 1956 L. O. STANLEY APPARATUS FOR COATING METAL ARTICLES Filed July 51, 1952 8 Sheets-Sheet 1 INVENTOR LESLIE 0. ST fi a? NLEY A a a A2 w Nov. 6, 1956 o. STANLEY APPARATUS FOR COATING METAL ARTICLES 8 Sheets-Sheet 2 Filed July 51, 1952 L 5/ E. L

Nov. 6, 1956 o. STANLEY 2,769,424

APPARATUS FOR COATING METAL. ARTICLES Filed July 51, 1952, 8 Sheets-Sheet 3 Hlii INVENTOR LESLIE O. STANLEY Nov. 6, 1956 L. o. STANLEY APPARATUS FOR COATING METAL ARTICLES 8 Sheets-Sheet 4 Filed July 31,-1952 IYNVENTOR LESLIE O. STANLEY Nov. 6, 1956 L. o. STANLEY APPARATUS FOR COATING METAL ARTICLES Filed July 51, 1952 8 Sheets-Sheet 5 INVENTOR LESLIE 0. STA

Nov. 6, 1956 o. STANLEY 2,769,424

APPARATUS FOR COATING METAL ARTICLES Filed July 31, 1952 8 Sheets-Sheet 6 Jifg: 15,

INVENTOR LESLIE O. STANLEY Nov. 6, 1956 o. STANLEY 2,769,424

APPARATUS FOR COATING METAL ARTICLES Filed July 31, 1952. 8 Sheets-Sheet 7 INVENTOR LESLIE O. STANLEY Nov. 6, 1956 STANLEY 2,769,424

APPARATUS FOR COATING METAL ARTICLES Filed July 51, 1952 8 Sheets-Sheet 8 INVENTOR LE SLIE- O. STANLEY United States Patent 2,769,424 APPARATUS FOR COATING METAL ARTIoLEs Leslie 0. Stanley, St. Clairsville, Ohio, assignor to Wheeling Steel Corporation, Wheeling, W. Va., a corporation of Delaware Application January 31, 1952, Serial No. 269,211

34 Claims. (Cl. 11856) This invention relates to coating metal articles and comprises a number of features of improvement in the fabrication of coated hollow metal products.

The art of coating metal objects with another dissimilar metal has long been practiced. Its practice makes possible the coating of a base metal with a metal having a more attractive surface, a greater resistance to corrosion or some other desired advantage. One of the oldest methods of coating hollow metal objects is that of hand dipping the object to be coated in a bath of molten flux and then into a bath of molten coating metal. Hand dipping is slow and expensive but has been continually practiced up to the present time for the production of most high quality coated hollow metal objects. For example, it is still the general practice in the galvanizing art to hand dip pails, wash tubs, garbage cans and the like when a continuous coating on both the inside and outside of the article is desired. Several mechanical methods of coating such hollow metal objects by dipping in molten metal have been proposed but have not been satisfactory for numerous reasons. All of the proposed methods of mechanical dipping have resulted in discontinuities in the coating metal or otherwise damaged coatings, and incomplete fiuxing of the object prior to coating as well as other faults which made the resulting ware less attractive and less resistant to the attacks of corroding materials.

I provide an apparatus which overcomes the objectional feature of mechanical dipping methods heretofore proposed and which produces coated ware equal in quality to that produced by hand dipping. I provide an apparatus for coating hollow metal objects having an opening into the interior thereof comprising a tank of molten metal having a portion thereof covered with molten flux, means for grasping a hollow object to be coated and carrying it through an arcuate path extending from a point above the portion of the molten metal covered with flux to a point beneath the portion of molten metal not covered by flux, means entering the opening in the hollow object at the end of the arcuate path and removing the object from the grasping and carrying means and means carrying the object from the molten bath to a discharge point outside the tank while leveling the coating metal on the object and removing the excess coating metal.

The machine which I have selected for the purpose of illustrating my invention provides means for grasping the hollow object to be coated at spaced apart points on the exterior thereof. Means are provided for carrying the object and the grasping means through a path such that the opening into the hollow metal object to be coated enters the molten flux prior to total submergence of the article and remains open to the flux until the entire object has passed through the flux and entered the metal.

The grasping means is preferably in the form of a yoke carrying stainless steel rollers spaced apart at substantially equal distances. These rollers preferably grasp the article in the swedge adjacent the bottom or base of the article. The yoke is then moved through an are so that it enters the flux on a line such that the flux flows into the interior of the hollow article and contacts all parts of both the exterior and interior surfaces of the article ahead of the molten metal. The movement of the yoke is then continued through the molten metal until the object is in a position with the opening uppermost and beneath the portion of molten metal not covered by flux. 7

In the embodiment illustrated the yoke is mounted on an end of a curved arm the other end of which is fixed to a rotatable shaft extending transversely across the top of the tank of molten metal. This shaft is positively driven for rotation in both directions to carry the curved arm into and out of the metal on the tank.

The means entering the opening and removing the object from the grasping means is provided with means for contacting the interior of the object at spaced apartpoints and for removing it from the yoke. Conveniently this means may be in the form of tongs, provided with two fixed downwardly and outwardly extending fingers and a movable finger. The movable finger is arranged so that movement into contact with the object being coated draws the object out of the yoke and into contact with the fixed fingers. v

Means are provided for continuously rotating the removing means after it has engaged the interior of the object and removed it from the yoke. The rotary movement is preferably about an axis through the center of the opening in the object. This rotary movement tends to level the coating on the object and assures a smooth continuous coating.

The removing means and the object engaged by it are lifted out of the molten metal and carried to aposition outside the tank where the object is discharged to a conveyor means which may be a continuous belt. In the drawings the removing means are shown mounted onthe end of a lifting arm the opposite end of which is fixed to a rotatable shaft extending transversely across the top of the tank parallel to the shaftcarrying the curved arm and yoke.

Means are provided for rotating the removing means and the object through an arc of about about the end of the lifting arm during the time that the object is being carried from the molten metal to the discharge point. This permits excess metal to drain from the interior of the object and at the same time positions the object for discharge onto the conveyor means. In order to assure that all of the excess metal is discharged from the coated object means are provided to impart a sudden reversal, followed by a forward acceleration to this rotary movement at a point in the rotation where the opening is free to discharge all of the molten metal from all surfaces of the object. This results in a kick which discharges the excess metal in and on the object away from it.

During the coating operation metal oxides and impurities collect on the surface of the molten metal from which the coated article emerges. Inorder to prevent this accumulated dross or scum from coming into contact with the coated object, I provide scraper means on the tank to draw this scum of oxide away from the portion of the surface through which the article emerges. The scraper means may be an arm mounted for rotation about one of its ends and carrying a blade in contact with the bath of molten metal.

Connections and timing means are provided by means of which each element of the apparatus is caused to operate in proper timed relationship. Preferably the connections are from a source of hydraulic fluid under pressure through hydraulic valves operated by spaced cam surfaces on a single shaft. The cam shaft may be connected to an electric motor through a reducing gear and a one revolution clutch so that each element of the apparatus 'hydraulicconnections shown in Figure 1;

I have not attempted to detail all of the novel features ofmy invention in the above summary but have simply drawn attention to particular features and have outlined the advantages thereof. Other details, objects and advantages of the invention will become apparent as the following description of a present preferred embodiment thereof and a present preferred method of practicing the same proceeds.

In the accompanying drawings I have shown a present preferred form of apparatus embodying the apparatus features of my invention and have illustrateda present preferred method of practicing the invention in which 7 Figure 1 is a side elevation of an apparatus for coating hollow objects with'molten coating metal;

Figure 2 is a top plan view of the apparatus of Fig- .ure -1;

' Figure 3 is a top plan view of the timing'means shown in Figure l; 1

Figure 4 is an end view of the timing means of Figure 3;

.Figure 5 is a somewhat diagrammatic plan view of 'Fi'g'ure 6 is an end view Iin'th'e timing means;

Figure 7 is a side elevation of the shown inFigure 1;

Figure 8 is a section of the line VIII-VIII of Figure 7; Figure 9 is a section on the line IXIX of Figure 7; Figure 10 is a section on the line XX of Figure7; Figure 11 is a partial plan view of the drawing gear and rack for the scraper blade shown in Figure 2;

Figure 12 is in partial elevation of the scraper blade of a cam wheel such as used lifting arm shaft and. driving mechanism therefor shown in Figure '2;

. Figure 1-3 is a fragmentary section of the lifting shaft at its junction with the lifting arm shown in Figures 1 and 2; V

Figure 14 is a fragmentary section of the end of the lifting arm at the removing means as shown in Figures 1 and 2; V

Figure 15 is a fragmentary section of the removing means shown'in'Figure 1;

Figure 16.is a side elevation'of the meansfor rotating the removing means'about the end of the lifting arm of Figure 1;

Figure 'ure 'l6;

17 is a section on theline XV1'IXVII of Fig- Figure 18 1s a top plan view partly cut away showing therotating means of Figure 16;

Figure 19.is a dia'grammatical illustration of the motion of the coated object at the/time the kick is imparted; Figure 20 is a diagrammatical illustration of theaction 0f the movable finger in removing the object from the yoke; .and'

Figures 21-28 diagrammatically illustrate the several relative positions of the coated object, the grasping means i-top of the t'ank above the molten coating Trnetal is journaled for rotation at eachside of the tankin bearings 14 land l5imou'nted onithetank. 'A'pinion gear ll6-is mounted 'on'one end of the shaft 13 'in engage'ment with-a pair-of 'rack gears .17 and18 on'opposite sides thereof. Guide members "19 and 20 partially surround the rack gears 17 and 18 where-they contact the'pinion gear 16 andmain- 4 nected to a source of hydraulic fluid 22 through a dual valve 23.

The valve 23 is actuated by a cam surface 24 on a portion of molten metal which is not covered with'flux,

as shown in Figure .26. A yoke 31 is fixed to the end of the curved arm 39 opposite its attachment to the shaft 13. Stainless steel rollers 32 are'mounted at spaced apart points on the yoke so that the rollers at the extremities of the. yoke are beyond the center line of the base of the article or object 33 to be coated. The rollers 32 are beveled on their peripheries so as to form a line contact with the object being held by them. Preferably the rollers 32 are arranged to engage the article to be gripped in the 'swedge which is usually formed adjacent the bottom of such hollow objects. The arm 39 is curved to a shape which causes the article grasped in the yoke to enter the flux 11 ona line such that the flux flows into the interior of .the object and contacts all parts of both interior and exterior surfaces prior to their contact with .the molten metal. Continued movement of the arm 3% places the object 33 in an upright position on the opposite side of the iflux fence 12 from the starting position.

A. second shaft 34 extending transversely across the top of the tank 10 parallel to thefirst shaft 13 is rotatably mounted in bearings 35 and 36 mounted on the tank 10. A pinion gear 37 is fixed on one end of the shaft 34 and is driven by two vertical'rack gears 38 and 39 on opposite sides thereof. Guide members 40 and 41 partiallysurround the rack gears 38 and 39 and maintain them' in contact with the pinion gear 37. Each of these rack .gears is driven by hydraulic cylinders 42 connected to the source of hydraulic fluid 22 by a dual valve 43.

The valve .43 like valve 23 previously described is operated by a cam surface 44 on the shaft 25. The cam surface 24 which actuates the valve 23 and the cam surface 44 which actuates the valve 43 are arranged-onthe shaft 25 so that the movements of the shafts 13 and 34 are properly timed with respect to each other.

Aninterior supporting arm 45 extends outwardly from V the shaft 34 and rotates with the shaft through an are extending from a-position above and substantially para}.

"lel to the surface of molten metal which is not covered by flux to aposition extending beyond an edge of the tank. A set of tongs 46 having fixed fingers 47 and a movable finger .48 project transversely outwardly from and removing means of Figure 1 astheobjectis-carried the end of the arm 45. The tongs 46 are mounted on the end of'a hollow-shaft 49. which surrounds the arm 45' and is supported thereby. The end of this hollow shaft 49 adjacent the shaft 34 is provided with a-pinion gear 50. A rack gear 51 is axially'movable above. the shaft 34 in contact with the pinion 50 to rotateit. The rack 51 is held in position above and in contact with the pinion 50 by means of a guide member 52 attached to the shaft 34. The rack 51 is actuated by means of a spring-loaded shaft 53 which is connected to a hydraulic cylinder 54. The hydraulic cylinder 54 is in turn actu-, ated by hydraulic fluid delivered from the source .of hydraulic fluid 22 through a valve 55.

Thegvalve 55 like the valves 23 and 43 previously dea scribed is operated by a cam surface 56 on the shaft 25.

I The cam 56 is provided with a cam surface which actuates the valve 55. The cam surface is provided with. a

portion which suddenly reverses the flow of hydraulic tain them'in' engagementwith the pinion, thusproviding a more'positive'drivefor the shaft 16. Each of the rack "gears -17 "and 18 is driven by hydraulic cylinders 21 confluid and then again reverses the flow of fluid thereby suddenly reversing the motion and then accelerating forward the motion of the shaft 53 which imparts a snap" or kick to the tongs. This snap tends to throw off excess molten metal from the coated object to leave a smooth finished coat. The cam surface is arranged on the shaft 25 so that the movement of the rack 51 and consequently the movement of the coated object is properly timed with respect to the movement of the shaft 34. A second hollow shaft 57 extends through the interior of the arm 45 from end to end and is provided with flanged collars 58 and 59 at each opposite end. A bell crank 60 is mounted on the interior of the housing 61 which is fixed to the end of the hollow shaft 49 and surrounds the operating mechanism of the tongs. One end 62 of the bell crank is in engagement with the flanged collar 58. The opposite end of the bell crank 69 is provided with a yoke 63 which engages pins 64 extending transversely from a shaft 65 which engages the end of the movable finger 43. The flanged collar 59 on the opposite end of the hollow shaft 57 is in engagement with the end of a second bell crank 66 which is mounted in the interior of the shaft 34. The opposite end of the bell crank 66 is provided with a yoke 67 which engages transverse pins 68 through an operating shaft 69 extending axially through the center of the shaft 34. The shaft 69 is connected to a hydraulic cylinder 70 which is actuated by hydraulic fluid from the source of hydraulic iluid 22 through a valve 71 operated by a cam 72 on the shaft 25. The cam surface is so arranged with respect to the cam surfaces operating the shafts 13 and 34 that the movement of the shaft 69 is properly timed with respect to the various movement of the other operative members of the structure.

A shaft 73 extends axially through the hollow shaft 57 and is provided with bevel gears 74 and 75 at its opposite ends. One of these bevel gears 74 is within the housing 61 which surrounds the operating mechanism for the tongs. This bevel gear 74 engages a bevel gear 76 mounted on a hollow shaft 77 which is connected to the fixed fingers 47 of the tongs. The shaft 77 is journaled for rotation in bearing blocks 78 and 79 mounted in the housing 61. The bevel gear 75 at the opposite end of the shaft 73 is in engagement with a bevel gear 89 on the end of a shaft 81 which extends axially through the shaft 34. The opposite end of shaft 81 is connected to a hydraulic motor 82 through a universal connection 83. The hydraulic motor 82 is in turn driven by fiuid from the source of hydraulic fluid 22 delivered through suitable lines to the hydraulic motor 82. A cam 86 is mounted on the shaft 81 at a point adjacent the universal joint 83. The cam 86 is provided with a depression 87 into which a locking member 88 is forced by a hydraulic cylinder 89 mounted transversely to the shaft 81. The movement of the hydraulic cylinder 89 is controlled by a valve 90 which is in turn controlled by a cam surface 91 on the shaft 25. The cam surface is arranged on the shaft so that the movement of the hydraulic cylinder 89 is in proper timed relation with the balance of the structure to stop the rotation of the shaft 81 and release it. The stopping mechanism 0n the shaft 81 is provided so as to permit an interruption in the rotation of the tongs while the object being handled is picked up and discharged. The cam surface and locking member are arranged so as to stop the tongs with the movable finger in position to remove the next object from the yoke. This prevents the movable finger from stopping at a position in which it cannot force the object from the yoke.

A skimmer 92 is mounted on the side of the tank w to sweep across the surface of that portion of the molten metal which is not covered with flux. The skimmer 92 thus removes the dross from the portion of the surface through which the coated article is to be withdrawn. The skimmer 92 is mounted on a vertical shaft 93 which is provided with a pinion gear 94. A rack gear 95 is mounted in contact with the pinion 94 and is held in position by a keeper 96. The rack 95 is connected to a shaft 97 which is movable along the side of the tank to rotate 6 the pinion and thereby the skimmer 92. The shaft 97 is actuated by an eccentric cam 98 on the shaft 34 (see Figure 10), the rotation of the cam imparting motion to the skimmer 92 through the shaft 97, rack gear and pinion gear 94.

The sequence of operations of the structure of this invention is best described with reference to Figures 21 through 28 of the drawings. When the article to be coated is placed in the yoke it is in the position shown in Figure 21. As the coating step proceeds the curved arm 39 carries the article to be coated through an arcuate path about the rotating shaft 13 so that the article enters the molten flux and passes into the molten metal with the interior and exterior of the article coated with flux prior to the time when it enters the metal. At the same time, the arm 45 on the shaft 34 is being rotated into position above the molten bath as shown in Figures 22, 23, 24 and 25. When the article to be coated reaches the end of its arcuate path about the shaft 13 the fingers 47 and 4-8 of the tongs enter the interior of the article and the movable finger 48 is actuated so that it draws the article from the yoke 31 into contact with the fixed fingers 47 (see Figures 20 and 26). The arm 30 and yoke 31 are then returned by the rotating movement of the shaft 13 to their loading position as in Figure 21. At the same time the tongs begin both to rotate about the end of the shaft 45 and about the end of the shaft 77 (see Figure 27). As the tongs rotate the arm 45 is itself rotated about the shaft 34 so that the coated article is carried through an arcuate path (see Figure 28) to a point outside the tank where it is discharged to a conveyor (see Figure 21) or other suitable means for carrying the finished article away from the mechanism.

While I have illustrated and described a present preferred embodiment of the invention and have illustrated :a present preferred method of practicing the same, it is to be distinctly understood that the invention is not limited thereto but may be otherwise variously embodied and practiced within the scope of the following claims.

I claim:

1. An apparatus for coating hollow metal objects having an opening into the interior thereof, comprising a tank of molten metal having a portion thereof covered with molten flux, means for grasping a hollow object to be coated and carrying it through an arcuate path extending from a point above the portion of the molten metal covered with flux to a point beneath the portion of molten metal not covered by flux wherein the object is entirely submerged in the molten metal, means entering the opening in the hollow object at the end of the arcuate path of the grasping and carrying means, said means removing the object from the grasping and carrying means while the object is entirely submerged in the molten metal, means carrying the object from the molten bath to a discharge point outside of the tank of molten metal and means acting simultaneously with the removing and carrying means leveling the coated metal on the object and removing the excess metal.

2. An apparatus for coating hollow metal objects having an opening into the interior thereof, comprising a tank of molten metal having a portion thereof covered with molten flux, means engaging the hollow object to be coated at spaced apart points on the exterior thereof and carrying it successively through the molten flux and into the molten metal to a point beneath the molten metal not covered by flux wherein the object is entirely submerged in the molten metal, means entering the opening in the hollow object and removing the object from the engaging means while the object is entirely submerged in the molten metal, means carrying the object from the molten bath to a discharge point outside the tank and means acting simultaneously with the carrying means leveling the coating metal on the object and removing excess coating metal.

3. An apparatus for coating hollow metal articles having anopening into the interior thereof, comprising 'a tank of molten metal, means on said tank for maintaining a layer of molten flux over a part of the surface of said molten metal, means on said tank for grasping at spaced apart points on the exterior thereof a hollow metal object to be coated, means for carrying the grasping means and article therein through an arcuate path-extending from a a point above the layer of flux to a point beneath the portion of the molten metal which is not covered by flux, said areuate path being such that the opening into the hollow metal object to be coated enters the molten flux prior to totalsubrn'ergence of the article and remains open to the flux until the entire object has passed beneath the.

flux and entered the metal, removing means entering the opening and engaging at spaced apart points the interior of the 'hollow object to remove the object from the grasp- -ing means at the point beneath the molten'rnetal while the object is entirely submerged in the molten metal, means for carrying'the removing-means through an arcuate path -from thepoint where it engages the interior of the hollow object to a point outside the tank, means for continuously rotating the object about a line through the center thereof and means removing excess metal from the object-duringits rotation.

4. An apparatus for coating hollow objects having an openinginto the interior thereof; comprising a tank containing a bath of liquidcoatingmaterial, 'meansfor grasping a hollow-object to be coated and carrying it through an arcuate path extending above the liquid coating materizil-to'a-poin-t beneath the liquid coating material whereinthe object is entirely submerged in the molten metal,

removing the excess therefrom.

"5. Anapparatus for [coating hollow'metal-objects having an opening-into the interior thereof, comprising a tank .eonta'ining a bath of molten metal having a portion there- 'ofeoveredwithmolten-flux, a pair of arms extending over said -tank and pivoted to movein a plane generally transverse to the surface of 'the'molten metal, grasping means onone of' said arms engaging the exterior of the hollow object to be coated, means for movingsaid arm and grasp- V ing'means through an arcuate pathex-tending from a point abovethesurface of the-moltenbath to a point beneath t-he surface ofsai'd bath wherein the object is entirely sub- -merged in the molten metal, removing means on the other arm entering the opening in the hollow object and engaging the'interior' thereof to remove it from the graspingmea-ns while the object is entirely submerged in the molten metal, means for carrying said second arm and removing means through an arcuate path to deposit the coated objectat a point outside the molten bath, means for ast-ing on the object to level the coating metal thereon arid-remove the excess therefrom.

6. 'An apparatus for coating hollow metal objects hav- 'ingan-openinginto the interior thereof, comprising a tank molten fiux, a-pa-ir of arms extending over said tank and pivoted to move in a plane generally transverse to the surface of the molten metal, a yoke on the end of one of said arms engagingthe hollow object to be coated at spaced apart points-on the exterior thereof, means for rotating said arm *and object carried thereby through an arcuate p'a th beginning at .a point above the bath of molten flux and exten'din'g intothe molten metal to a point beneath it e po'r-ti'on' of molten metal notcovered with flux whereitnithecobjectis' entirely submerged in .the molten metal,

means on the end of the other of said arms enteringIthe opening in the hollow obiect'atatheend' f h rcua path, engaging the'interior thereof and removing it from the yoke while the object is entirely submerged in'the surface of the molten metal, a yoke on the end ofone of said arms, rollers spaced apart on the interior of the yoke to engage the exterior of the hollow object to be coated, said arm being curved so that rotation about its end opposite the yoke causes the coated object to follow an armate path such that the opening into the hollow metal objeet enters the molten flux prior to total submergence of the object and remains open through the flux until'the entire object has passed beneath the flux and entered the molten metal to terminate in a position beneath the portion of molten metal not covered by flux and with the opening into the object adjacent said surface, means for rotating said arm about its end, removing means on the other arm entering the opening into the hollow object and engaging the interior thereof to remove it from the rollers in the yoke, means for carrying the second arm in rotation about its end opposite the removing means, said means carrying the second arm through a path to deposit the coated object at a point outside the molten bath, means acting on the object to level the coating metal thereon and remove the excess therefrom during its removal from metal bath and prior to being deposited outside the bath. 8. An apparatus for coating hollow objects having an opening into the interior thereof, comprising a tank of 7 liquid coatingmaterial, a pair of arms extending over said tank and pivoted to move in a plane generally transverse to the surface of the coating material, grasping means on one of said arms engaging the'exterior of a hollow object to be coated, means for moving said arm.

and grasping means through an arcuate path extending from a point above the surface of the coating material to a point beneath the surface of said coating material wherein the object is entirely submerged in the molten metal, a

plurality of fingers mounted on the end of the otherarm for rotation about said'arm, said fingers extending genk erally radially outwardly from said 'arm and adapted to enter the opening in the hollow object and engage the -of molten metal having a portion thereof covered with 7 interior thereof to remove it from the grasping means while the object is entirely submerged in the molten metal, means for carrying said other arm through an arcuate path to deposit the coated object at *apoint outside the molten bath, means for rotating the fingers about the end of said arm and means instantaneously accelerating the rotation of said fingers whereby todisc'harge from the object excess coating material held thereon. V

9. An apparatus for coating hollow metal objects'having an opening into the interior thereof, comprising a tank of coating material, a pair of arms extending over said tank and pivoted to move in a plane generallytransverse to the surface of the coating material, grasping means on one of said arms engaging the exterior of' the hollow objeet to be coated, means for moving said arm and grasping means through an arcuate path extending from a point above the surface of the coating material to a point beneath the surface of said material wherein .the object is entirely submerged'in the molten metal, a plurality of fingers mounted for rotation aboutthe end of the other arm, said fingers extending generally radially outwardly from said arm and entering the opening in the hollow ob ject, means for moving one of said fingers abouta pivot adjacent the end of said arm whereby to engage the interior of the hollow object and draw it out of engagement 'with thegrasping means and into engagement with the 7 remaining fingers while the object .is entirely submerged in the molten metal, means for carrying said other arm through an arcuate path to carry the fingers to a point outside the bath of coating material and means for acting on the object to level the coating material thereon and remove the excess therefrom during its removal from the coating material and prior to its being deposited outside the bath.

10. An apparatus for coating hollow metal objects having an opening into the interior thereof, comprising a tank of molten metal having a portion thereof covered with molten flux, 2. pair of rotatable shafts extending across the top of said tank, an arm on each of said shafts extending over said tank and rotatable with the shafts in a. plane generally transverse to the surface of the molten metal, grasping means on one of said arms engaging the exterior of the hollow object to be coated, means for rotating said one shaft so as to carrying the grasping means on the end of the arm through an arcuate path extending from a point above the surface of the molten metal to a point beneath the portion of the molten metal not covered by flux and terminating with the hollow object in an upright position with the opening therein adjacent the surface of the bath, a plurality of fingers mounted on the end of the other of said arms for rotation about said arm, said fingers extending generally radially outwardly from said arm and adapted to enter the opening in the hollow object and to engage the interior thereof to remove it from the grasping means, means for rotating said other arm and shaft to remove the object from the bath and deposit it outside the molten bath, connections between the means for moving the said one shaft and the means for moving the said other shaft whereby the fingers are carried into the interior of the hollow object immediately at the end of the arcuate path of the grasping means.

ll. An apparatus for coating hollow metal objects having an opening into the interior thereof, comprising a tank of molten metal having a portion thereof covered with molten flux, a pair of rotatable shafts extending across the top of said tank, an arm on each of said shafts extending over said tank and rotatable with the shafts in a plane generally transverse to the surface of the molten metal, grasping means on one of said arms engaging the exterior of the hollow object to be coated, means for rotating said one shaft so as to carry the grasping means on the end of the arm through an arcuate path extending from a point above the surface of the molten metal to a point beneath the portion of the molten metal not covered by flux and terminating with the hollow object in the upright position in the opening therein adjacent the surface of the bath, a plurality of fingers mounted on the end of the other of said arms for rotation about said arm, means for moving one of said fingers about a pivot adjacent the end of said arm whereby to engage the interior of the hollow object and draw it out of engagement with a grasping means and into engagement with the remaining fingers, means for rotating said other shaft and arm through an arcuate path to carry the object from the coating metal to a point outside the bath, connections between the means for rotating said one shaft and the means for rotating said other shaft whereby the fingers are inserted into the opening in the hollow object immediately at the end of the arcuate path of the grasping means and the movable finger is caused to draw the object out of engagement with the grasping means and into engagement with the other fingers.

12. An apparatus for coating hollow metal objects having an opening into the interior thereof, comprising a tank of molten metal having a portion thereof covered with molten flux, a pair of rotatable shafts extending across the top of said tank, an arm on each of said shafts extending over said tank and rotatable with the shafts in a plane generally transverse to the surface of the molten metal, grasping means on one of said arms engaging the exterior of the hollow object to be coated,'nieans for fd= tating said one shaft so as to carry the grasping means on the end of the arm through an arcuate path extending from a point above the surface of the molten metal to a point beneath the portion of the molten metal not covered by flux and terminating with the hollow object in the upright position in the opening therein adjacent the surface of the bath, a plurality of fingers mounted on the end of the other of said arms for rotation about said arm, said fingers extending generally radially outwardly from said arm and adapted to enter the opening in the hoiiow object and to engage the interior thereof to remove it from the grasping means, means for rotating said other arm and shaft to remove the object from the bath and deposit it outside the molten bath, connections between the means for moving the said one shaft and the means for moving the said other shaft whereby the fingers are carried into the interior of the hollow object immediately at the end of the arcuate path of the grasping means, means for acting on the object to level the coating material thereon and remove the excess therefrom during its travel from the coating material to a position outside the bath, means connecting the connections between the two shafts with the leveling means whereby said last mentioned means begins to operate upon the coated object as soon as the fingers have engaged its interior and removed it from the grasping means.

13. An apparatus for coating hollow metal objects having an opening into the interior thereof, comprising a tank of molten coating material, a pair of arms extending over said tank and pivoted to move in a plane generally transverse to the surface of the coating material, grasping means on one of said arms engaging the exterior of the hollow object to be coated, means for moving said arm and grasping means through an arcuate path extending from a point above the surface of the coating material to a point beneath the surface of said material, a plurality of fingers mounted for rotation about the end of the other arm, said fingers extending generally radially outwardly from said arm and entering the hollow object to be coated, means for rotating said fingers about the end of the arm, means for carrying said other arm through a path to remove the coated object from the bath and deposit it outside said bath, connections between the means for rotating said one arm and said other arm, connections with the means for rotating said fingers about the end of said other arm whereby the rotation of the fingers begins when the fingers move the object from the grasping means and means accelerating momentarily the rotation of said fingers about the end of said other arm whereby excess coating material is discharged from the object.

14. An apparatus for coating hollow objects having an opening into the interior thereof, comprising a tank of liquid coating material, a pair of arms extending over said tank and pivoted to move in a plane generally transverse to the surface of the coating material, grasping means on one of said arms engaging the exterior of the hollow object to be coated, means for moving said arm and grasping means through an arcuate path extending from a point above the surface of the coating material to a point beneath the surface of said coating material, a plurality of fingers mounted on the end of the other arm for rotation about the end of said arm, said fingers extending generally radially outwardly from said arm and adapted to enter the opening in the hollow object and engage the interior thereof to remove it from the grasping means, means for carrying said other arm through an arcuate path to remove the object from the bath and deposit it at a point outside the bath, a skimmer blade reciprocable across the surface of the molten coatin g metal to remove dirt and impurities from the surface of the bath just prior to the introduction of the fingers into the interior of the hollow .object and connections between the means for rotating the two arms whereby the fingers are inserted into the opening in the hollow object .at the end of the arcuate path of'the grasping means and said skimmer blade is passed across the surface of the bath just preceding the introduction of the fingers into the opening.

15. An apparatus for coating hollow metal objects having .an opening into the interior thereof, comprising a tank of molten metal having a portion thereof covered with molten flux, means engaging the hollow object to be coated at spaced apart points on the exterior thereof and carrying it successively through the molten flux and into the molten metal to .a point beneath the molten metal not covered by flux, -means.entering the opening in the i hollow object and removing the object from the engaging means, means carrying the object from the molten bath to a discharge point outside the tank, skimmer means reciprocable across the surface of the molten metal not. covered by flux removing dirt and impurities therefrom and connections between said skimmer means and the means removing the object from the grasping means whereby said skimmer means is passed across the surface of the bath prior to the entry 'of the removing means into the object. 7 V

16. An apparatus for coating hollow metal objects having an opening into the interior thereof, comprising a tank of molten metal having a portion thereof covered with molten flux, a source of fluid under pressure, means grasping the hollow object to be coated and fluid driven means carrying the grasping rneans successively through the molten flux and 'into the molten metal to a point beneath 'the molten metal not covered with flux, means entering the opening in the hollow object and engaging the interior thereof, fluid driven .means removing'the engaging means and the object from the molten bath and carrying them to a point outside the tank, connections between the source of fluid under pressure and each of the fluid driven means delivering fluid under pressure to said fluid driven means and control means between the source of fluid under pressure and each of the fluid driven means whereby said means are caused to operate in proper timed relationship.

17. An apparatus for coating hollow metal objects having an opening into the interior thereof, comprising a tank of molten metal having a portion thereof covered with molten flux, a source of fluid under pressure, means grasping the hollow object to be coated and fluid driven means carrying the grasping means successively through the molten flux and into the molten metal to a point beneath the molten metal not covered with flux, means entering the opening in the hollow object and engaging the interior thereof, fluid driven means removing the engaging means and the objectfrorn the molten bath and carrying them to a point outside the tank, connections between the source of fluid under pressure and each of the fluid driven if means delivering fluid under pressure to said fluid drive means, valve means in said connections between the source of fluid and each of said fluid driven means and cam means openingiand closing said valve means in timed re-' 'lationship whereby the engaging means enters the opening in the hollow object immediately upon the object reaching the point beneath the molten metal notcovered by flux.

18. An apparatus for coating hollow objects having an opening into the interior thereof, comprising a tank contaming a bath of liquid coating material, a pair of arms extending over said tank and pivoted to move in a plane generally transverse to the surface of the coating ma terial.,: fluid pressure means pivoting said arms, grasping means on one of the arms engaging the exterior of a hollow object to be coated, a plurality of fingers mounted on the end of the other arm .for rotation about said arm,

said fingers'eX-tending generally radially outwardly from ,saidarm and adapted to enter the opening in the hollow object and engage the interior thereof to remove it from V of which rollers engage the object on the side 12 V the grasping means, fluid pressure, means actuating said fingers to engage the interior of the hollow object, 'fluid pressure means carrying. said other arm throughan :arcuate path to deposit a coated object at :a point outside the molten bath, a source of fluid under pressure, control means between the source of fluid under pressure and each of the fluid. pressure means regulating the flow of fluid thereto whereby to control their'operation in proper mean-s pivoting said arms, grasping means onone ofthe arias engaging the exterior of a hollow object to :be coated,

.a plurality of fingers mounted on the :end of the other arm for rotationabout said .arm, said fingers extending generally radially outwardly from said arm and adapted to enter the opening in the hollow object and engage the interior thereof to. remove it from the .graspingmeans, fluid pressure means actuating said fingers toengage the interior of the hollow object, fluid pressure means carryingsaid otheriarm through an arcuate path to deposit a coated object at a point outside the molten bath, a source of fluid under pressure, connections delivering fluid under pressure to each of the fluid pressure means, valve means in each of said connections and means opening and closing said valves to regulate the flow of fluid to the fluid pressure means whereby to control their operation in proper timed sequence. 7

20. Anapparatus for coating hollow objects havingan opening into the interior thereof, comprising a tank" of "liquid coating material, a pair of arms extendingaover said tank and pivoted to move in a plane generally transverse to the surface of the coating material, fluid pressure means pivoting said arms, grasping means on one of the arms engaging the exterior of a hollow object to be coated to carry it to a point beneath the surface of the coating material, a plurality of fingers mounted on the ,end of the otherrarm for rotation about said arm, said fingers extending generally radially outwardly from said arm and adapted to enter the opening in the hollow object and engage the interior thereof to remove it from the grasping means, fluid pressure means actuating said fingers to engage the interior of the hollow object, fluid pressure means carrying said other arm through an .arcuate path to deposit a coated object at a point outside the molten bath, :a source :of fluid under pressure, connections 7 delivering fluid under pressure to each of the fluid pressure means, valve means in each of said connections, a cam follower on eachof said valves and cam means opening and closing said valves in timed relationship whereby the fingers sequentially enter the opening in the object and engage the interior thereof immediately upon the object reaching the point beneath the surface of the coating material. 7

21. In an apparatus for coating hollow objects having an opening into the interior thereof by passing the object through a layer of molten flux and into a'bat-h of coating material, an arm extending over said bath and pivoted to move in a plane generally transverse to the surface of the coating material, a yoke on one end of said arm, spaced apart rollers on said yoke frictionaliy engaging the object to be coated at spaced apart point-s thereon, at least two of its center line opposite the throat of the yoke and means for moving said arm and yoke through an arcuate path extending from a point above the surface of the bath to a point below the surface of said bath wherein the object is entirely submerged in the molten metal, said arcuate path being such that theopening in the hollow object enters the molten flux prior to total submergence of the article-and remains open to the flux .until the entire object has passed beneath the flux and entered the molten metal.

22. In an apparatus for coating hollow objects having an opening into the interior thereof by passing the object into a bath of coating material, an arm extending over said bath of coating material and pivoted to move in a plane generally transverse to the surface of the coating material, a plurality of fingers mounted on the end of said arm for rotation about the end thereof, said fingers extending generally radially outwardly from said arm and adapted to enter the opening in the hollow object and to engage the interior thereof at spaced apart points, means for carrying the arm through an arcuate path to remove the coated object from the bath and deposit it at a point outside the bath, means for rotating the fingers about the end of said arm and means instantaneously accelerating the rotation of said fingers whereby to discharge from the object excess coating material held thereon.

,23. An apparatus for coating hollow objects having an opening into the interior thereof, comprising a tank of liquid coating material, a pair of arms extending over said tank and pivoted to move in a plane generally transverse to the surface of the coating material, fluid driven means pivoting one of said arms about one end thereof, grasping means on the end of said arm opposite the pivot engaging the exterior of a hollow object to be coated, a plurality of fingers mounted on the end of the other arm for rotation about said arm, said fingers extending generally radially outwardly from said arm and adapted to enter the opening in the hollow object and engage the interior thereof to remove it from the grasping means, fluid pressure means actuating said fingers to engage the interior of the hollow object, fluid pressure means carrying said other arm through an arcuate path to deposit a coated object at a point outside the molten bath, a source of fluid under pressure, valve means between the source of fluid under pressure and each of the fluid driven means regulating the flow of fluid thereto, cam follower means actuating said valve means, cam means in contact with said follower means, said cam means mounted on a rotating shaft rotating at substantially constant speed whereby to control their operation in proper timed sequence.

24. An apparatus for coating hollow objects having an opening into the interior thereof, comprising a tank of liquid coating metal, a layer of molten flux on a part of the surface of said tank, a pair of arms extending over said tank and pivoted to move in a plane generally transverse to the surface of the coating metal, fluid driven means pivoting one of said arms so that the end opposite the pivot moves through an arcuate path from a point above the molten flux to a point beneath the molten metal not covered by flux, grasping means on the end of said arms opposite the point engaging the exterior of a hollow object to be coated, a plurality of fingers mounted on the end of the other arm for rotation about said arm, said fingers extending generally radially outwardly from said arm and adapted to enter the opening in the hollow object when it reaches the point beneath the molten metal not covered by flux and to engage the interior thereof to remove it from the grasping means, fluid pressure means actuating said fingers to engage the interior of the hollow object, fluid pressure means carrying said other arm through an arcuate path to deposit a coated object at a point outside the molten bath, a source of fluid under pressure, valve means between the source of fluid under pressure and each of the fluid driven means regulating the flow of fluid thereto, cam follower means on said valve means and rotary cam means in contact with the cam followers opening and closing the valves whereby to control the movements of the fluid driven means.

'25. An apparatus for coating hollow objects having an opening into the interior thereof, comprising a tank of liquid coating material, a pair of substantially parallel shafts extending over said tank in a plane substantially parallel to the surface of the coating material and journaled for rotation, a pinion gear on an end of each of said shafts, rack gear means engaging said pinion gears,

fluid pressure means moving said rack gear means transversely to said shafts to rotate the shafts, an arm extending transversely outwardly from each of said shafts and movable in a plane generally transverse to the surface of the coating material, grasping means on one of the arms engaging the exterior of a hollow object to be coated, a plurality of fingers mounted on the end of the other arm for rotation about said arm, said fingers extending generally radially outwardly from said arm and adapted to enter the opening in the hollow object and engage the interior thereof to remove it from the gasping means, fluid pressure means actuating said fingers to engage the interior of the hollow object, fluid pressure means carrying said other arm through an arcuate path to deposit a coated object at a point outside the molten bath, a source of fluid under pressure, control means between the source of fluid under pressure and each of the fluid driven means regulating the flow of fluid thereto whereby to control their operation in proper timed sequence.

26. An apparatus for coating hollow objects having an opening into the interior thereof, comprising a tank of liquid coating material, a pair of substantially parallel shafts extending over said tank and journaled for rotation thereon in a plane substantially parallel to the surface of the coating material, a pinion gear on one end of each of said shafts, rack gear means engaging said pinion gears, fluid pressure means moving said rack gear means in contact with the pinion gears to rotate said shafts, a curved arm extending transversely outwardly from one of said shafts, a yoke on the end of said arm removed from the shaft, a plurality of spaced apart rollers on said yoke engaging the exterior of an object to be coated, said arm and yoke being arranged to receive the object to be coated in the inverted position and to carry it into the coating material to a point beneath the surface thereof on the side of the said one shaft opposite the receiving position with the opening uppermost, a second arm extending transversely outwardly from the other shaft, a plurality of fingers mounted on the end of the other arm for rotation about said arm, said fingers extending generally radially outwardly from said arm and adapted to enter the opening in the hollow object at the point beneath the surface of the coating material and engage the interior thereof to remove it from the grasping means, fluid pressure means actuating said fingers to engage the interior of the hollow object, a source of fluid under pressure, control means between the source of fluid under pressure and each of the fluid pressure means regulating the flow of fluid thereto whereby to control their operation in proper timed sequence.

27. An apparatus for coating hollow objects having an opening into the interior thereof, comprising a tank of liquid coating material, a pair of substantially parallel shafts extending over said tank and journaled for rotation thereon in a plane substantially parallel to the surface of the coating material, a pinion gear on the end of each of said shafts, rack gear means engaging said pinion gears, fluid pressure means moving said rack gear means in contact with the pinion gears to rotate said shafts, an arm extending radially outwardly from one of said shafts, grasping means on said arm engaging the exterior of the article to be coated, said arm and grasping means being arranged to receive a hollow object to be coated and to carry it into the coating material to a point beneath the surface with the opening into the object being uppermost, a second arm extending radially outwardly from the other shaft, a rotatable sleeve surrounding said arm, fluid pressure means rotating said sleeve, a plurality of fingers fixed on one end of said sleeve to rotate with the sleeve about the end of the second arm, said fingers extending generally radially outwardly from said arm and adapted to enter the opening in the hollow object at the point beneath the surface, fluid pressure means moving one of said fingers into engagement with the interior of the object to remove the object from the grasping means and e in the hollow object at the said shaft and the fingers to rotatethe fingers about a common axis, a source of fluid under pressure and control means between the source of fluid under pressure and each of the fluid pressure means regulating the flow of fluid thereto whereby to control their operation in proper timed sequence.

'28. An apparatus for coating hollow objects having an opening into the interior thereof, comprising a tank of liquid coating material, a pair of substantially parallel shafts extending over said tank and journaled for rotation thereon in a plane substantially parallel to the surface of the coating material, a pinion gear on the end of each of said shafts, rack gear means engaging said pinion gears, fluid pressure means moving said rack gear means in con tact with the pinion gears to rotate said shafts, an arm extending radially outwardly from one of said shafts, grasping :means on said arm engaging'the exterior of the article to be coated, said arm and grasping means being arranged to receive a hollow object to be coated and to carry it into the coating material to .a point beneath the surface with the opening into the object being uppermost, a second arm extending radially outwardly from the other shaft, a rotatable sleeve surrounding said arm, fluid pressure means rotating said sleeve, a plurality of fingers fixed on one end of said sleeve to rotate about the end of the second'arm, said fingers extending generally radially outwardly from said arm and adapted to enter the opening in the hollow object at the point beneath the surface, fluid pressure means moving one of said fingers into engagement with the interior of the object to remove the object from the grasping means and bring it into engagement with the other fingers, a cam surface'on said other shaft, a follower mounted thereon and connected to rack means slidable on tie tank, a pinion gear rotatably mounted on the tank adjacent the bath in engagement with said rack means, a skimmer arm fixed to said pinion gear and extending over a portion of the surface of the coating material and in contact therewith, a source of fluid under pressure and control means between the source of fluid under pressure and each of the fluid pressure means regulating the flow of liquid thereto whereby to control their operation in proper timed sequence.

29 An apparatus for coating hollow objects having an opening into the interior thereof, comprising a tank of liquid coating material, a pair of substantially parallel shafts extending over said tank and journaled for rotation thereon in a plane substantially parallel to the surface of the coating material, a pinion gear on the end of each of said shafts, rack gear means engaging said pinion gears, fluid pressure means moving said rack gear means in contact with the pinion gears to rotate said shafts, an arm extending radially outwardly from one .of said shafts, grasping means on said arm engaging the exterior of the article to be coated, said arm and grasping means being arranged to receive a hollow object to be coated and to carry it into the coating material to a point beneath the surface with the opening into the object being uppermost, a second arm extending radially outwardly from the other shaft, a rotatable sleeve surrounding said arm, flui-d pressure means rotating said sleeve, a plurality of fingers fixed on one end of said sleeve to rotate about the end of the second arm,

wardly from said arm and adapted to enter the opening point beneath the surface,

said fingers extending generally radially outfluid pressure means moving one of said fingers into -engagement with the interior of the object to remove the ob ect fromthe grasping means and bring it into engage ment with the other fingers, a source offluid under pressure, connections from the source of fluid under pressure to each of the fluid pressure means, .a valve in said connections between'the source of fluid and each fluid pressure means, aicam follower operatively connected to each valve, cam means equal valves mounted on a common rotatable shaft in engagement with the cam followers and means for rotating said cam shaft whereby to operate thevalves in proper timed sequence.

30. An apparatus for coating hollow objects having an opening into the interior thereof, comprising a tank zof liquid coating material, a pair of substantially parallel shafts extending over said tank and journaled for rotation thereon in a plane substantially parallel to the surface of the coating material, a pinion gear on thepend of each of said shafts, rack gears means engaging said pinion gears, fluid pressure means moving said rack gear means in contact with the pinion gears to.rotate said 7 shafts, an armtextending radially outwardly from one of said shafts, grasping means on said arm engaging the exterior of the article to be coated, said armand'grasping means being arranged to receive a hollow objectto be coated and to carry it into the coating material to a point beneath the surface with the opening into the object being uppermost, a second arm extending radially outwardly from the other shaft, a rotatable sleeve surrounding said arm, fluid pressure means rotating said sleeve,

a plurality of fingers fixed on one end of 'said sleeve to rotate about the end of the second arm, said'fi lger-s sex 7, i tending generally radially outwardly from said arm and adapted to enter the opening in the hollow object at the, 7

point beneath the surface, fluid pressure means moving one of said fingers into engagement with the interior of the object to remove the object from the grasping means and bring it into engagement with the other fingers, ,a rotatable shaft through the center of said second ,arm, fluid pressure means rotating said shaft, geartmeans connecting said shaft and the fingers to rotate the fingers about a common axis, a source of fluid under pressure,

connections from the source of fluid under pressure to each of the fluid'pressureimeans, a valve in said 169111360,

tions between the source of fluid and each fluid pressure means, a cam follower operatively connected to each valve, cam means equal in number to the number of valves mounted on a common rotatable shaft in engagement with the cam followers and means for rotating said cam shaft whereby to operate the valves in proper timed sequence. 7 v

31. An apparatus for coating hollow objects having an opening into the interior thereof, comprising a tank of liquid coating material, a pair ofsubstantiallypamllel shafts extending over said tank and journaled forirotation thereon in a plane substantially parallel to the .surface, of the coating material, a pinion gear on the-end of each of said shafts, rack gear means engaging said pinion gears, fluid pressure gmeans moving said rack gear means in contact with the pinion gears to rotate said shafts, an arm extending radially outwardly from :one of said shafts, grasping means on said arm engaging the exterior of the article to be coated, said arm and grasping means being arranged to receive :a hollow object to be coated and to carry it into the coating material to a point beneath the surface with the opening into the .ob-

ject being uppermost, a second arm extending radially outwardly from the other shaft, a rotatable sleeve surrounding said arm, fluid pressure means rotating said a sleeve, a plurality of fingers fixed on one end of said sleeve to rotate about the endof the second am, said fingers extending generally radially outwardly from said arm and adapted to enter the opening in the hollow object at the point beneath the surface, fluidt pressure' means moving one of said fingers into engagement with the interior of the object to remove the object from the on the tank, a pinion gear rotatably mounted on the tank adjacent the bath in engagement withlsaidrack means, a skimmer arm fixed to said pinion gear andextending in nnmberto the number of V over a portion of the surface of the coating material and in contact therewith, a source of fluid under pressure, connections from the source of fluid under pressure to each of the fluid pressure means, a valve in said connections between the source of fluid and each fluid pressure means, a cam follower operatively connected to each valve, cam means equal in number to the number of valves mounted on a common rotatable shaft in engagement with the cam followers and means for rotating said cam shaft whereby to operate the valves in proper timed sequence.

32. An apparatus for coating hollow objects having an opening into the interior thereof, comprising a tank of molten coating metal having a portion thereof covered with molten flux and a pair of substantially parallel shafts extending over said tank and journaled for rotation thereon in a plane substantially parallel to the surface of the coating metal, a pinion gear on the ends of said shafts, rack gear means engaging said pinion gears, fluid pressure means moving said rack gear means in contact with the pinion gears to rotate said shafts, an arm extending radially outwardly from one of said shafts, grasping means on said arm engaging the exterior of the article to be coated, said arm and grasping means being arranged to receive a hollow object to be coated and to carry it from a point above the molten flux to a point beneath the surface of the coating material not covered by flux with the opening into the object being uppermost, a second arm extending radially outwardly from the other shaft, a rotatable sleeve surrounding said arm, fluid pressure means rotating said sleeve, a plurality of fingers fixed on one end of said sleeve to rotate about the end of the second arm, said fingers extending generally radially outwardly from said arm and adapted to enter the opening in the hollow object at the point beneath the surface, fluid pressure means moving one of said fingers into engagement with the interior of the object to remove the object from the grasping means and bring it into engagement with the other fingers, a source of fluid under pressure and control means between the source of fluid under pressure and each of the fluid pressure means regulating the flow of fluid thereto whereby to control their operation in proper timed sequence.

33. An apparatus for coating hollow objects having an opening into the interior thereof, comprising a tank of molten coating metal having a portion thereof covered with molten flux and a pair of substantially parallel shafts extending over said tank and journaled for rotation thereon in a plane substantially parallel to the surface of the coating metal, a pinion gear on the ends of said shafts, rack gear means engaging said pinion gears, fluid pressure means moving said rack gear means in contact with the pinion gears to rotate said shafts, an arm extending radially outwardly from one of said shafts, grasping means on said arm engaging the exterior of the article to be coated, said arm and grasping means being arranged to receive a hollow object to be coated and to carry it from a point above the molten flux to a point beneath the surface of the coating material not covered by flux with the opening into the object being uppermost, a second arm extending radially outwardly from the other shaft, a rotatable shaft through the center of said second arm, fluid pressure means rotating said shaft, gear means connecting said shaft and the fingers to rotate the fingers about a common axis, a source of fluid under pressure and control means between the source of fluid under pressure and each of the fluid pressure means regulating the flow of fluid thereto whereby to control their operation in proper timed sequence.

34. An apparatus for coating hollow objects having an opening into the interior thereof, comprising a tank of molten coating metal having a portion thereof covered with molten flux and a pair of substantially parallel shafts extending over said tank and journaled for rotation thereon in a plane substantially parallel to the surface of the coating metal, a pinion gear on the ends of said shafts, rack gear means engaging said pinion gears, fluid pressure means moving said rack gear means in contact with the pinion gears to rotate said shafts, an arm extending radially outwardly from one of said shafts, grasping means on said arm engaging the exterior of the article to be coated, said arm and grasping means being arranged to receive a hollow object to be coated and to carry it from a point above the molten flux to a point beneath the surface of the coating material covered by flux with the opening into the object being uppermost, a second arm extending radially outwardly from the other shaft, a cam surface on said other shaft, a follower mounted thereon and connected to rack means slidable on the tank, a pinion gear rotatably mounted on the tank adjacent the bath in engagement with said rack means, a skimmer arm fixed to said pinion gear and extending over a portion of the surface of the coating metal not covered with flux and in contact therewith, a source of fluid under pressure and control means between the source of fluid under pressure and each of the fluid pressure means regulating the flow of liquid thereto whereby to control their operation in proper timed sequence.

References Cited in the file of this patent UNITED STATES PATENTS 2,133,213 Scott Oct. 11, 1938 2,150,274 Gingell Mar. 14, 1939 2,245,425 Aungst June 10, 1941 2,259,728 Bridges Oct. 21, 1941 2,282,898 Snader et al. May 12, 1942 2,368,130 Pox Jan. 30, 1945 2,477,684 Borg et al Aug. 2, 1949 2,573,660 Brownell Oct. 31, 1951 

